This invention relates to a sleeve and bushing assembly and, in particular, to a sleeve and bushing assembly for use in mounting the ends of a shock absorber to a motor vehicle. The invention also relates to a method of manufacturing sleeve and bushing assemblies.
Sleeve and bushing assemblies have been used in the past for mounting a shock absorbers to motor vehicles. Such assemblies generally comprise an elastomeric bushing having an axial bore therethrough. A tubular, cylindrical sleeve extends through the axial bore. An eye ring radially encircles the bushing and is welded or otherwise fastened to the end of the shock absorber. Then the tubular sleeve is fit over a threaded stud on the vehicle body and secured in place with a threaded nut.
The above described, prior assemblies generally function for the purpose intended, and they have the advantage of being easy, and thus relatively inexpensive, to manufacture. Additionally the sleeves used in these prior assemblies may be made of different lengths for spacing the assemblies different distances away from the vehicle body if such spacing is desired.
These above described, prior assemblies have, however, several significant disadvantages. The bushing is allowed to and does move along the sleeve under load. Further the bushing has to be made from relatively "stiff" durometer materials, and this impairs the ability of the bushing to isolate vibrations and road noises. Also if spacers are required, the selection and placement of the spacer(s) are left to the discretion of the person who is installing the shock absorber on the motor vehicle, as opposed to the manufacturers of the sleeve and bushing assembly.
One proposed solution to the disadvantages of the above described, prior assemblies has been to dispose retaining washers on either side of the bushing and to stake or flare the ends of the sleeve to hold the washers in place. While this does prevent the bushing from moving along the sleeve, it makes the assembly more difficult to manufacture because two staking operations are required.
Another disadvantage with this proposed solution is that sleeves of differing lengths can be used by automotive technicians which results in changes in the amount of compression of the elastomeric bushing. Additionally, such prior sleeves require that each end must be staked to hold the retaining washers in place. If it is desired to mount the shock absorber a further distance away from the vehicle body than the length of the sleeve permits, spacers or washers must be used to achieve the desired distance, creating an opportunity for mounting error during assembly.